采用从头算(ab initio)和密度泛函理论(DFT B3LYP)方法。对二(2-苯基-8-羟基喹啉)锌(Zn(qPh)2)及其衍生物的基态结构进行优化,同时用ab initio HF单激发组态相互作用(CIS)法在6-31G基组上优化其最低激发单重态几何结构,用含时密度泛函理...采用从头算(ab initio)和密度泛函理论(DFT B3LYP)方法。对二(2-苯基-8-羟基喹啉)锌(Zn(qPh)2)及其衍生物的基态结构进行优化,同时用ab initio HF单激发组态相互作用(CIS)法在6-31G基组上优化其最低激发单重态几何结构,用含时密度泛函理论(TD-DFT/B3LYP)及6-31G基组计算吸收和发射光谱。计算表明,该类物质电子在基态与激发态间的跃迁,主要是电子云分布由定域化向离域化的转变。吸收及发射光谱的计算值与实验值基本符合。该类化合物的电子亲和能较大,都是优良的电子传输材料,改变中心金属原子对配合物光谱性质影响不大。而羟基氧被硫原子取代后,化合物的吸收光谱产生明显红移。展开更多
3-Acetyl-4-hydroxyl coumarin was synthesized by acetylation and acyl chlorination of salicylic acid followed by the cyclocondensation of acetacetic ester. Its condensation with each of three （aldehydes）, N,N-dimethy...3-Acetyl-4-hydroxyl coumarin was synthesized by acetylation and acyl chlorination of salicylic acid followed by the cyclocondensation of acetacetic ester. Its condensation with each of three （aldehydes）, N,N-dimethy-4-aminobenzaldehyde, N,N-di（4-methyphenyl）-4-aminobenzaldehyde and （N,N-）diphenyl-4-aminobenzaldehyde affords three 4-hydroxyl coumarin derivatives, i.e., 3\[（para-（dimethyamino））-cinnhyl\]-4-（hydroxyl） coumarin\1\], 3{\[para-di（4-methyphenyl）amino\]-cinnhyl}-4-（hydroxyl） coumarin\2\], and （3\[（para-）diphenylamino）-cinnhyl\]-4-hydroxyl coumarin\3\]. The three derivatives have high extinction （coefficients） in UV-vis absorption, which were 5.25×104 L/（mol·cm）, 3.39×104 L/（mol·cm）, and 3.24×104 L/（mol·cm）, respectively, and intensive luminescence in both the THF solution and solid state. Derivatives TM1 and TM2 emit intensive orange red luminescence with the same absorption peak at （500 nm） and the identical small Stoke shift of 85 nm in the emission spectra in THF. The photoluminescence peaks of the three derivatives in solid state are at 705, 643, and 660 nm, （respectively）. Derivative TM3 displays intensive red luminescence with the peak at 486 nm and a large Stoke shift of 152 nm in the emission spectrum in THF, which makes it a novel red luminescent material that may be used in OLEDs.展开更多
以羟基苯甲醛衍生物和丙二酸为原料,吡啶为溶剂,六水哌嗪为催化剂,通过Knoevenagel缩合反应合成五种羟基肉桂酸。采用熔点分析法、核磁共振氢谱法(_1H Nuclear Magnetic Resonance,_1H NMR)、红外光谱法(IR)、高效液相色谱法(HPLC)对产...以羟基苯甲醛衍生物和丙二酸为原料,吡啶为溶剂,六水哌嗪为催化剂,通过Knoevenagel缩合反应合成五种羟基肉桂酸。采用熔点分析法、核磁共振氢谱法(_1H Nuclear Magnetic Resonance,_1H NMR)、红外光谱法(IR)、高效液相色谱法(HPLC)对产物的结构和纯度进行鉴定,结合对Fe^(3+)还原能力、清除DPPH自由基能力等体外抗氧化方法进行抗氧化活性实验,并与羟基苯甲醛衍生物、2,6-二叔丁基-4-甲基苯酚(BHT)和肉桂酸的抗氧化能力进行对比。结果表明:分别得到目标产物——3,4-二羟基肉桂酸、4-羟基-3-甲氧基肉桂酸、3-羟基-4-甲氧基肉桂酸、4-羟基肉桂酸、3-羟基肉桂酸,纯度分别为92.45%、93.14%、99.55%、96.54%、93.50%;3,4-二羟基肉桂酸、4-羟基-3-甲氧基肉桂酸对Fe^(3+)还原能力、清除DPPH自由基能力较强,均高于BHT,且对DPPH自由基的IC_(50)值(半抑制浓度)分别为(11.50±0.02)、(16.57±0.04)、(33.04±0.03)μg/m L;酚羟基是羟基肉桂酸衍生物的抗氧化活性中心,具有邻苯二酚结构或者羟基邻位存在给电子基团的衍生物,具有较高的抗氧化活性;4'位羟基取代衍生物比3'位羟基取代衍生物的抗氧化活性强;苯环上的α,β-不饱和酸共轭结构可以提高酚类化合物的抗氧化活性。展开更多
文摘采用从头算(ab initio)和密度泛函理论(DFT B3LYP)方法。对二(2-苯基-8-羟基喹啉)锌(Zn(qPh)2)及其衍生物的基态结构进行优化,同时用ab initio HF单激发组态相互作用(CIS)法在6-31G基组上优化其最低激发单重态几何结构,用含时密度泛函理论(TD-DFT/B3LYP)及6-31G基组计算吸收和发射光谱。计算表明,该类物质电子在基态与激发态间的跃迁,主要是电子云分布由定域化向离域化的转变。吸收及发射光谱的计算值与实验值基本符合。该类化合物的电子亲和能较大,都是优良的电子传输材料,改变中心金属原子对配合物光谱性质影响不大。而羟基氧被硫原子取代后,化合物的吸收光谱产生明显红移。
文摘3-Acetyl-4-hydroxyl coumarin was synthesized by acetylation and acyl chlorination of salicylic acid followed by the cyclocondensation of acetacetic ester. Its condensation with each of three （aldehydes）, N,N-dimethy-4-aminobenzaldehyde, N,N-di（4-methyphenyl）-4-aminobenzaldehyde and （N,N-）diphenyl-4-aminobenzaldehyde affords three 4-hydroxyl coumarin derivatives, i.e., 3\[（para-（dimethyamino））-cinnhyl\]-4-（hydroxyl） coumarin\1\], 3{\[para-di（4-methyphenyl）amino\]-cinnhyl}-4-（hydroxyl） coumarin\2\], and （3\[（para-）diphenylamino）-cinnhyl\]-4-hydroxyl coumarin\3\]. The three derivatives have high extinction （coefficients） in UV-vis absorption, which were 5.25×104 L/（mol·cm）, 3.39×104 L/（mol·cm）, and 3.24×104 L/（mol·cm）, respectively, and intensive luminescence in both the THF solution and solid state. Derivatives TM1 and TM2 emit intensive orange red luminescence with the same absorption peak at （500 nm） and the identical small Stoke shift of 85 nm in the emission spectra in THF. The photoluminescence peaks of the three derivatives in solid state are at 705, 643, and 660 nm, （respectively）. Derivative TM3 displays intensive red luminescence with the peak at 486 nm and a large Stoke shift of 152 nm in the emission spectrum in THF, which makes it a novel red luminescent material that may be used in OLEDs.
